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Discussion Starter #1 (Edited)
I changed out the front thrust arm bushings, and ball joints today, so I figured I'd make a DIY for it. I'd been experiencing a clicking up front under change in fore-aft loading (braking, acceleration, direction), and with the subframe bolts tight, figured I'd change out the thrust arm bushings and ball joints. My car has 152k miles of upstate NY winters, so either way, a parts refresh wouldn't hurt. (*full disclosure: the replacement parts did nothing to stop the clicking, but I found the driver's side outer CV boot torn, so I have a new axle shaft on order; I'll replace the transverse control arms at the same time (I've had a spare set collecting dust on the shelf for 5 years).

Tools needed:
-ratchet, breaker bar, torque wrench
-22mm socket
-21 mm socket (13/16" works fine)
-21mm wrench (13/16" wrench works fine)
-T40 Torx socket
-E12 socket
-BFH (I use a 3 lb lump hammer)
-pickle fork
-chisel
-long punch
-sawzall (or hacksaw)

1) Raise front of vehicle, support on jack stands. I used the jack pad under the engine and then put the stands under the subframe, inline with the transverse control arm attachment points. Remove wheels and engine shield. Spray PB Blaster into the ball joint bore in the bottom of the steering knuckle now.
IMG_5172.jpg IMG_5181.jpg

2) Locate the thrust arm; it runs fore-aft from the steering knuckle forward to the subframe. Before working on it, remove the two 8mm screws and the upper 10mm nut that hold the plastic lower shield in place; you'll need it free in order to wrestle the bushing's bolt out. The bolt and nut are 21mm (13/16") and the lock nut that holds the arm to the ball joint is 22mm. Brake torque on the TA nut/bolt; I had to shock the wrench with the lump hammer to brake it free. Remove the nut but leave the bolt in place.
IMG_5173.jpg IMG_5174.jpg IMG_5179.jpg

3) Next, move to the ball joint. I used a pneumatic impact gun to shock the 22mm ball joint nut loose and remove it. If you don't have one, you'll need to use a 22mm box wrench on the nut and the T40 socket to hold the ball joint stud in order to remove the lock-nut. Remove the nut. Using the pickle fork* and the BFH, separate the arm from the ball joint. (If you are saving the ball joint, use a ball joint press instead; the pickle fork will destroy the ball joint). Swing down the arm, and remove the bolt. My socket shown below looks in rough shape, because I modified it years ago by grinding flats on opposite sides in order to hold it with an open end wrench to do the above job, as I don't have a 22mm box wrench. T40 fits inside the 3/8" square drive hole.
IMG_5175.jpg IMG_5176.jpg IMG_5177.jpg IMG_5178.jpg

4) Using the E12 socket, remove the 2 bolts per ball joint that hold them. Now be prepared for a long time of beating metal. Alternating between hammering a chisel between the ball joint and the steering knuckle from the bottom, and hammering a long punch onto the top of the ball joint through the ball joint bore from above (where you sprayed the rust penetrant earlier), keep working until the ball joint gets freed
IMG_5181.jpg IMG_5182.jpg

5) I'm cheap, so I chose to save something like $150 by just replacing the bushings. THE BUSHINGS MUST BE CLOCKED IN THE ARMS A SPECIFIC WAY. Mark the arm and bushing with a sharpie and then transcribe the mark to the new bushing. If you forget to do this, notice that the bolt carrier is shaped like a triangle, with a key way at the apex. The triangle aligns with the direction of the thrust arm, with the keyway pointing away from the thrust arm.
I unfortunately didn't have an adapter perfectly the same diameter as the bushing to press it out of the arm, so I went old-school and dirty:
-using the press and a socket, I pressed the rubber bushing out of its sleeve (a bunch of fluid came out in the process).
IMG_5184.jpg
-Using a piece of heavy duty square stock, I then pressed the sleeve down flush to the thrust arm.
-I then secured the arm in a vice, and CAREFULLY cut the bushing sleeve with a sawzall (a hacksaw blade would work too, and be safer) lengthwise all the way through, stopping before cutting into the thrust arm. Then using a chisel, I folded the sleeve so it would fall out. On the second one, I used the chisel and a hammer to drive the sleeve out without folding it, as I'd realized it would work great to remove bushings in the future without going through the above steps. The new bushing easily pressed in (after a coating of grease on the sleeve), as it is wider than the thrust arm, so no adapter needed. Triple check the bushing's clocking.
IMG_5183.jpg

6) Installation is the reverse of the removal.

Tips:
DO NOT FULLY TIGHTEN THE BUSHING BOLT/NUT UNTIL THE VEHICLE IS ON THE GROUND. I jacked it up high enough to put 6x6 cribbing beneath the tires so that I could get both suspension compression, as well as space beneath the car to swing the wrench.
-Clean out the ball joint bores with a wire brush and sandpaper before installing the new joints.
-I used Motorcraft nickel antisieze lathered liberally all over the ball joint cap and stud prior to installation.
-I torqued the ball joint bolts (replacements were T40 IIRC) to 45 ft-lbs
-I torqued the lock nut to 50 ft-lbs
-The best I could find for the specs on the bushing nut/bolt is 50 lb-fts +90* torque angle, which implies the bolts are stretch and one time use. I didn't have replacements, so I simply tightened the nuts until the torque felt about the same as that needed to remove them. As I have to get back under there for the axle and transverse arms, I'll most likely replace the bolts with grade 8 at that time.
 

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Nice write up. When I did this, I couldn't get the lower ball joints out for love nor money. I finally was able to free them up by using an air chisel. If you can impact them on the outer metal ring rather than directly on top of the ball joint, it seems to work better.
 

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Anti-Hack
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Discussion Starter #3
Nice write up. When I did this, I couldn't get the lower ball joints out for love nor money. I finally was able to free them up by using an air chisel. If you can impact them on the outer metal ring rather than directly on top of the ball joint, it seems to work better.
Yeah, my driver's side was a bear. Chisel between the plate and knuckle, punch on the plate now that it's been raised to twist the ball joint in the bore and break the rust, punch from above. I had to make a few different length punches from 5/8" round stock, and repeated drives with the BFH eventually resulted in the sweet sound of the old joint slamming the ground. In hindsight, I doubt I needed to replace any of the above, as they all had life left, but at 150k who knows how much life. If the ball joints weren't in such close proximity to the CV boots I would have taken the MAP torch to them from the beginning, but I didn't want to damage the boots. It turns out, one is damaged, and may be the cause of my symptoms all along.
 

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Discussion Starter #4
FYI, Advance Auto sells brand new front axles, fully assembled, for under $60. Ordered online for the 20% discount coupled with a $5 coupon, free shipping to my door plus tax, my nice shiny $47.56 axle and CV joints just arrived. Is it OEM quality? Not for a 6th of the price. It seems decent quality though, (I’ll see how it holds up) and importantly (to me) isn’t a reman. And with the lifetime warranty it’ll be the last one axle I’ll ever have to buy, even if it fails... an exchange at the store down the road is much easier than shipping back and days lost...axle’s swapped in an afternoon and wheels back turning.


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Thank you for posting the DIY. I'm having a hard time getting the ball joint out -- what a PITA!

I removed the driver's side, front forward control arm and the bushing is definitely shot. I pounded on the ball joint for hours, but can't get it out. I soaked it with penetrating oil and will try again tomorrow.

Can any of you that posted go into more detail of how you got the ball joint out? I'm considering taking the whole knuckle off to press it out.

Here's a few shots of my progress...

IMG_0483.jpg

IMG_0484.jpg

IMG_0485.jpg
 

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TA
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Thank you for posting the DIY. I'm having a hard time getting the ball joint out -- what a PITA!

I removed the driver's side, front forward control arm and the bushing is definitely shot. I pounded on the ball joint for hours, but can't get it out. I soaked it with penetrating oil and will try again tomorrow.

Can any of you that posted go into more detail of how you got the ball joint out? I'm considering taking the whole knuckle off to press it out.

Here's a few shots of my progress...

View attachment 845339

View attachment 845341

View attachment 845343
I had a terrible time as well removing the ball joint. I wound up buying a air impact hammer and driving it out from the top. It seemed like you had to try to hit the top of the joint on the edge where the sleeve is rather than the top center on the cap that covers the ball. It still took me a lot of hammering. Once it started to move, it popped right out.
 

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Discussion Starter #8 (Edited)
I kept at it with swaps between blows with the BFH on a chisel between the knuckle and the ball joint flange, and blows from above with a long rod. Now that the flange is all pealed up, hammer the chisel along the sides of the flange (90* from the bolts) at a slight angle to keep the chisel from walking out. A long chisel is easier to control (I have one that is about a foot long; if you have a bench grinder, you can make one from solid steel round stock). As Tim stated, once movement started, it popped right out. The axle does get in the way of direct blows, so you could always pop the strut, pull the axle from the hub, move it to the side, reattach the strut and achieve a better hammer angle, slightly less work than removing the entire knuckle.

When you put the new ones in, liberally coat them with antiseize; I prefer Nickel for most applications. Pick up a can from your nearest Ford dealer or order from Amazon. I don't like Aluminum antiseize for areas exposed to the weather as it tends to seize (aluminum + steel).

Heat can also be your friend... first on the ball joint from above to burn up any rust, then focused on the knuckle to get it to expand. Just be really careful you don't hit any rubber with the torch.

Are you replacing just the TA bushings or the entire arm?
 

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Mix yourself some acetone + atf fluid. Let it soak in that. Use maybe heat to expand the knuckle to aid in banging out the ball joint?
 

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This ball joint wants to stay with the X3, and is doing it's best. I purchased an air hammer today and went to work. The top of the ball joint is now obliterated and I focused on the top outer edges. I tore a CV boot in the process. It's small enough to fix with a bike tire patch kit.

I went to work on the bottom and moved it ~2mm farther out than yesterday. I finally hammered in a bit and tried to use a second floor jack to push the bit up and use it as a lever to pull it out the ball joint. It lifted up the X3 off the ground until the bit broke.

I'm out of air hammer bits now. The air hammer and BFH isn't working.

[Edit] Don't use MAP gas (heat) as someone else suggested unless you want to buy another control arm... [/Edit]

Progress...it did move more.

IMG_0487.jpg
 

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Try taking one of your used bits and cutting the end off of it so that it is just a flat round cross section. You should be able to concentrate the blows better and get it a bit more on the side.
 

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Discussion Starter #12
This ball joint wants to stay with the X3, and is doing it's best. I purchased an air hammer today and went to work. The top of the ball joint is now obliterated and I focused on the top outer edges. I tore a CV boot in the process. It's small enough to fix with a bike tire patch kit.

I went to work on the bottom and moved it ~2mm farther out than yesterday. I finally hammered in a bit and tried to use a second floor jack to push the bit up and use it as a lever to pull it out the ball joint. It lifted up the X3 off the ground until the bit broke.

I'm out of air hammer bits now. The air hammer and BFH isn't working.

[Edit] Don't use MAP gas (heat) as someone else suggested unless you want to buy another control arm... [/Edit]

Progress...it did move more.

View attachment 845469

What happened to the CA due to heat? Heat must always be used cautiously.

I forgot to mention earlier with the blows with the BFG: have a block of wood under the knuckle, with vehicle weight on it, so that all force is transferred to the ball joint, and not being absorbed by the strut.
 

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On mine the only way I could get it out was by taking the whole knuckle off and banging it out from the top, straight down, with a piece of pipe and a 2lb mini sledge hammer. Popped out with two blows. Mine was fused in with 10 years of snow and salt. Joys of living in the rust belt.
 

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Ball joint
I ended up repositioning the knuckle to get the ball joint out. I pulled the brake caliper aside and removed the rotor. I disconnected the tie rod end, rear control arm and separated the knuckle from the strut.

This gave me enough movement to really hammer on the top of the ball joint more directly. I used a jack to support the knuckle when it was free and did not remove the CV.

A few direct hits with a BiggerFH and the ball joint finally came out.

Front Control Arm Bushing
I used a piece of pipe and a lathe to create enough room for the control arm pushing to be pressed out. I set the control arm on this piece of pipe and used a large socket the was large enough to catch the metal edge of the busing, but small enough to pass through the control arm. A 50k pound press did the rest of the work.
 

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Discussion Starter #15
Ball joint
I ended up repositioning the knuckle to get the ball joint out. I pulled the brake caliper aside and removed the rotor. I disconnected the tie rod end, rear control arm and separated the knuckle from the strut.

This gave me enough movement to really hammer on the top of the ball joint more directly. I used a jack to support the knuckle when it was free and did not remove the CV.

A few direct hits with a BiggerFH and the ball joint finally came out.

Front Control Arm Bushing
I used a piece of pipe and a lathe to create enough room for the control arm pushing to be pressed out. I set the control arm on this piece of pipe and used a large socket the was large enough to catch the metal edge of the busing, but small enough to pass through the control arm. A 50k pound press did the rest of the work.
Nice. Just make sure to clock the new bushing correctly when you press the new one in. IIRC, the arrow on the bushing points away from but in line with the thrust arm if you didn't mark it on the arm.
 

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Discussion Starter #16 (Edited)
IIRC, the arrow on the bushing points away from but in line with the thrust arm if you didn't mark it on the arm.

Well I done remembered wrong, just now verified by crawling under my car to see what Id actually did, because I mixed up the reference points when typing my original post. Keyway/rubber arrow should be pointing aft, along with the triangular metal bolt sleeve. You’ll find that there is a piece of rubber at one point in the bushing that sits between the bolt sleeve and the outer sleeve, inside one of the holes in the center of the rubber: this is to resist compression while the strut is under tension and should be forward of the mounting bolt, horizontally. Factory arms have somewhat of an alignment arrow, but I don’t know that all aftermarket arms do. Better to set up the bushing based on its design IMO. Apologies for flipping my words. Powertools and fires go great with moonshine, the internet not so much...


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Now this is a good thread...I'm in the middle of this job. I want to simply change the control arm (thrust) bushings on both sides going to try to keep the ball joint in place and connected.

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Now this is a good thread...I'm in the middle of this job. I want to simply change the control arm (thrust) bushings on both sides going to try to keep the ball joint in place and connected.

Sent from my SM-J727T using Tapatalk
Me as well.

Duke, how hard was it to separate the control arm from the ball joint?
 

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Discussion Starter #19
Me as well.



Duke, how hard was it to separate the control arm from the ball joint?


Not hard at all. 2-3 blows with a lump hammer on the pickle fork and the arms dropped right off. I replaced the ball joints too so I didn’t care about damaging them with the fork, otherwise I would have pressed them off.


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I suspect it's a bit more tricky with leaving the ball joint in tact and only removing the bushing?

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